Findings from most in-depth study into UK parents who kill their children

Experts from The University of Manchester have revealed their findings from the most in-depth study ever to take place in the UK into the tragic instances of child killing by parents, known as filicide.

The research, published in journal PLOS ONE, found 37 per cent of parents and step-parents who killed their children were suffering from some form of mental illness and 12% had been in contact with mental health services within a year of the offence. Academics from the University's Institute of Brain Behaviour and Mental Health analysed 297 cases of convicted filicide and 45 cases of filicide-suicides in England and Wales occurring between January 1997 and December 2006 from the National Confidential Inquiry into Suicide and Homicide by People with Mental Illness (NCI) - a longitudinal national case series of all homicides in the UK, with particular focus on perpetrators with mental illness. The scope of the NCI’s clinical dataset enabled analysis of filicide to take place in greater detail than other epidemiological studies.

The over-representation of mental illness in filicide was the key finding of the study. Forty percent of filicide perpetrators had a recorded mental illness, consistent with findings from other smaller studies. But the most common diagnoses were mood disorders and personality disorder; not psychosis. This may contrast with popular perceptions and that of some professionals caring for mentally ill parents about more severe psychotic illnesses like schizophrenia. The proportion of perpetrators with psychosis was still high at 15%, (18% mothers) compared to 6% of homicides in general population studies. This compares to 0.4% overall prevalence in UK, 0.5% for women and 0.3% for men, with highest rates for women and men in people aged 35-44 years.

Less than half the perpetrators studied with mental illness had previous contact with mental health services; fewer fathers than mothers. Of the total, 20% were treated before the offence, which is lower than a similar Swedish population study (35%). Overall, the Manchester findings were consistent with those reported from a similar large, population-based sample in Denmark, where most parents committing filicide had no prior psychiatric history. This finding would suggest that the perpetrators were either not experiencing serious mental health problems at the time or, that they had not sought help.

Other key findings from the research were that 23% of female perpetrators were teenagers at the time of the child victim’s birth. In the general population, the proportion of babies born to a teenage mother was 7%. Overall, fathers were significantly more likely to kill their children than mothers, and were more likely to use violent methods of killing, have previous convictions for violent offences, perpetrate multiple killings, and have a history of substance misuse or dependence. Of the 297 total filicide cases recorded during the 10 year period, the study found 13% of perpetrators took their own life after killing their child;known as filicide-suicide.

The study also reported that victims were equally likely to be girls as boys. Infants were most likely to be victims rather than school aged or older children. The researchers say the high proportion of infant deaths strengthens calls for early assessment detection of post-partum mental illness - a condition which may be becoming more widespread.

Professor Kathryn Abel, who led the study, said: "Identifying associations between mental illness and filicide has clear implications for service providers. It shows there needs to be greater awareness for patients who are parents and especially those with severe mood disorders. This is an increasingly important issue because better mental health care means that more people with mental illness are able to become parents. Generating effective child violence/homicide prevention strategies requires broad public health approaches. Targeting sub-populations by providing high quality evidence about risk factors such as mental illness and the need for contact with mental health services may prove more constructive for health service development. Violence prevention may also offer possibilities to recognise and intervene with specific risk factors.

"Risk-assessment of mothers in joint psychiatric care reported greatest risk of actual harm to child was presented by mothers with mood disorders like depression, rather than schizophrenia. In spite of this, staff consistently perceived and rated mothers with schizophrenia to be the greatest risk to their infants and this was reflected in significantly higher rates of social service supervision on discharge compared to other ill mothers. Our findings indicate that fathers with a history of substance misuse, violence or mood disorder, and mothers who were teenagers at the birth of their child, or with mood disorder may be appropriate targets for intervention. Parents with mental illness should be asked about violent thoughts toward their children, particularly if depressed.”

The researchers conclude that understanding the risk factors for filicide and the widespread nature of child abuse is far from complete. Future research on filicide should study these acts in the context of child abuse and domestic violence to support the development of effective interventions, they suggest.

Notes for editors

The research was completed by Sandra Flynn, Professor Jenny Shaw from the Centre for Mental Health and Risk, and Professor Kathryn Abel, from the Centre for Women's Mental Health, based in the Institute of Brain Behaviour and Mental Health at The University of Manchester and is published in PLOS Journal.

To view the journal article in PLOS ONE, click here: http://dx.plos.org/10.1371/journal.pone.0058981 The NCI sample used is a 10-year consecutive case series of convicted homicides and homicide-suicides (01/01/97-31/12/06) in England and Wales. Homicides are defined as murder, manslaughter or infanticide under the Homicide Act (1957). Homicide-suicides are defined as cases where the suicide occurred no more than three days after the homicide. Filicides are homicides committed by a parent or adult in-loco parentis, with the victim aged under 18.